RESORPTION ATELECTASIS
• OBSTRUCTION BY: *MUCOUS OR MUCOPURULENT PLUG
(POST-OP, ASTHMA, BRONCHIECTASIS OR CHRONIC BRONCHITIS)
*TUMOUR. *FOEIGN BODY .
COMPRESSION ATELECTASIS
ACCUMOLATION OF :• FLUID (PLEURAL EFFUSION)• BLOOD (HAEMOTHORAX)• AIR (PNEUMOTHORAX)
ALL WITHIN THE PLEURAL CAVITY.
ACUTE LUNG INJURY
• BILATERAL PULMONARY DAMAGE.• ENDOTHELIAL AND EPITHELIAL DAMAGE.• DUE TO DIRECT OR INDIRECT LUNG INJURY.• ACUTE DYSPNEA + HYPOXEMIA + BILATERAL
PULMONARY INFILTRATES WITHOUT PRIMARY LEFT SIDED HEART FAILURE.
• CAN PROGRESS TO ACUTE RESPIRATORY DISTRESS SYNDROME.
MAIN CAUSES OF ACUTE LUNG INJURY
DIRECT LUNG DAMAGE :• PNEUMONIA.• ASPIRATION. INDIRECT LUNG INJURY :• SEPSIS.• SEVERE TRAUMA WITH SHOCK.
ACUTE RESPIRATORY DISTRESS SYNDROME: CLINICAL FEATUERES.
• LIFE THREATENING RESPIRATORY INSUFFICIENCY.
• CYANOSIS.• HYPOXEMIA REFRACTORY TO OXYGEN
THERAPY.• MAY PROGRESS TO MULTISYSTEM ORGAN
FAILURE.
CLINICAL FEATURES
• 80% DEVELOP ARDS WITHIN 72 HOURS OF THE INSULT.
• MORTALITY DECREASED FROM 60% TO 40% IN USA IN THE LAST DECADE.
• POOR PROGNOSIS:*OLD AGE.*SEPSIS.*MULTISYSTEM FAILURE.
OUTCOME
• SURVIVORS END WITH DIFFUSE INTERSTITIAL FIBROSIS.
• THIS CAUSES COMPROMISE OF RESPIRATORY FUNCTION.
• SURVIVALS WHO DON’T HAVE CHRONIC CONSEQUENCES RETAIN NORMAL RESPIRATORY FUNCTION WITHIN 6-12 MONTHS.
OBSTRUCTIVE VS RESTRICTIVE LUNG DISEASES
• OBSTRUCTIVE: LIMITATION OF AIRFLOW.
• RESTRICTIVE: REDUCED EXPANSION, AND DECRESED TOTAL CAPACITY.
EMPHYSEMA
• ABNORMAL, PERMANENT ENLARGEMENT OF AIR SPACES DISTAL TO TERMINAL BRONCHIOLES ALONG WITH DESTRUCTION TO THEIR WALLS WITHOUT SIGNIFICANT FIBROSIS.
PANACINAR EMPHYSEMAM
• MOSTLY AFFECTS LOWER LUNG ZONES.• ASSOCIATED WITH ALPHA 1 ANTITRYPSIN
DIFICIENCY.
CLINICAL FEATURES
• DYSPNEA .• WEIGHT LOSS.• PROLONGED EXPIRATION.• BLOOD GASES RELATIVELY NORMAL.• PINK PUFFERS
CHRONIC BRONCHITIS
PERSISTENT PRODUCTIVE COUGH FOR AT LEAST THREE CONSECUTIVE MONTHS FOR AT LEAST TWO CONSECUTIVE YEARS.
PATHOGENESIS
• HYPERSECRETION OF MUCUS.• DUE TO HYPERTROPHY OF MUCUS SECRETING
GLANDS IN TRACHEA AND MAIN BRONCHI.• INCREASE IN MUCIN SECRETING GOBLET
CELLS IN THE EPITHELIUM OF SMALL BRONCHIA.
ASTHMA
• CHRONIC INFLAMMATORY DISORDER WHICH CAUSES RECURRENT EPISODES OF WHEEZING, BREATHLESSNESS, COUGH, AND CHEST TIGHTNESS.
ASTHMA
INTERMITTENT, REVERSIBLE :• AIRWAY OBSTRUCTION.• CHRONIC BRONCHIAL INFLAMMATION WITH
EOSINOPHILS.• BRONCHIAL SMOOTH MUSCLE HYPERTROPHY
AND HYPERREACTIVITY.• INCREASED MUCUS SECRETION.
TYPES OF ASTHMA
• ATOPIC : • THE MOST COMMON TYPE.• BEGINS IN CHILDHOOD.• TYPE 1 HYPERSENSITIVITY REACTION.• POSITIVE FAMILY HISTORY.• TRIGGERED BY ENVIRONMENTAL ANTIGENS
OR INFECTIONS.
NON ATOPIC ASTHMA
• NO EVIDENCE OF ALLERGEN SENSITIZATION• SKIN TEST NEGATIVE.• POSITIVE FAMILY HISTORY IS LESS COMMON.• INFECTIONS COMMON.• VIRAL INFLAMMATION LOWERS THRESHOLD OF THE
SUBEPITHELIAL VAGAL RECEPTORS TO IRRITANTS.• HUMORAL AND CELLULAR MEDIATORS SIMILAR TO
ATOPIC ASTHMA.
DRUG INDUCED ASTHMA
• ASPIRIN • MECHANISM UNKNOWN• ASPIRIN INHIBITS COX WITHOUT AFFECTING
LIPOOXYGENASE PATHWAY SHIFTING THE BALANCE TO BRONCHOSPASM.
CLINICAL FEATURES
• SEVERE DYDPNEA AND WHEEZING.• LABOUR TO INSPIRE AND CAN NOT EXPIRE.
THIS RESULTSIN HYPERINFLATION.• ATTACKS LAST FOR 1 TO SEVERAL HOURS.
SARCOIDOSIS
• MULTISYSTEM DISEASE OF UNKNOWN ETIOLOGY.
• NONCASEATING GRANULOMAS IN MULTIPLE ORGANS.
• DIAGNOSIS: BY EXCLUSION.• NONCASEATING GRANULOMAS: *MYCOBACTERIA. *FUNGAL INFECTIONS. *BERYLLIOSIS.
• MAJOR PRESENTATION OF SARCOIDOSIS: BILATERAL HILAR LYMPHADENOPATHY AND/OR LUNG INVOLVEMENT.
• EYE AND SKIN INVOLVEMENT EACH OCCUR IN 25% OF CASES.
OUTCOME
• UNPREDICTABLE COURSE. • EITHER PROGRESSIVE CHRONICITY OR
RELAPSES AND REMISSIONS.• REMISSIONS ARE EITHER SPONTANEOUS OR
WITH STEROIDS.
TUBERCULOSIS
• INFECTIOUS DISEASE CAUSED BY MYCOBACTERIUM TUBERCULOSIS.
• CAUSES CASEATING GRANULOMAS.• MAINLY AFFECTS LUNGS, BUT OTHER ORGANS
CAN BE AFFECTED.
EPIDEMIOLOGY
• A LEADING CAUSE OF DEATH IN DEPRIVED COUNTRIES.
• WESTERN WORLD : DEATH DUE TO TB DECLINED IN THE 19TH CENTURAY .
• RESURGENCE OF CASES SINCE 1984 DUE TO HIV INFECTION.
• MORE PREVALENT IN IMMEGRANTS IN USA.
SYSTEMIC MILIARY TB
• BACILLI DISSIMINATE THRGH SYSTEMIC CIRCULATION.
• CAN AFFECT ANY ORGAN.• MAINLY: LIVER, BONE MARROW, SPLEEN,
ADRENALS, MENINGES, KIDNEYS, F.TUBES AND EPIDIDYMIS.
TUMORS
• LUNG CARCINOMA IS THE MOST COMMON CAUSE OF CANCER DEATH IN THE WEST.
• TYPES: SCC, ADENOCARCINOMA, SMALL CELL CARCINOMA AND LARGE CELL CARCINOMA.